Water jetting guns are known. One type of water jetting gun, also called a hand lance, has a dump tube. U.S. Pat. No. 5,349,982 discloses a water jetting gun having a dump tube. The gun has a gun housing or block. A valve cartridge is maintained within a valve chamber of the block. To service the valve cartridge inside the block, one must remove a dump adaptor from the block with a hand tool such a crescent wrench. One would use a hand tool to tighten the adaptor to the block to ready the gun for operation.
U.S. Pat. No. 5,636,789 also discloses a water gun with a dump tube. The gun has a shoulder support which is adjustable. The gun has a valve cartridge assembly which is removable from a housing with a hand tool. The hand tool couples with a hex head of the valve cartridge. One would use a hand tool to tighten the cartridge to the housing to ready it for operation.
Prior art FIGS. 1A-1B disclose a handle assembly 10 for a 15,000 psi water jetting gun. The handle assembly is configured for use with a dump tube 12. See FIG. 2B. The assembly has a body 14 which can be called a gun housing or a gun block. The body or housing holds a valve cartridge assembly 16 in a valve chamber 18 defined by the block 14. The chamber 18 has an access port 20 sealed off by an adaptor 22. The adaptor 22 is coupled to the valve cartridge 16 at a coupling end 23 of the adaptor. The coupling end 23 is threadably engaged to the block 14. The adaptor has a hex head 24 which rises above the block's external surface 26. The head 24 is configured for coupling to a hand tool such as a crescent wrench. An operator may remove the adaptor 22 and valve cartridge 16 coupled thereto by untightening the adaptor 22 from the block 14. The operator will use a hand tool. The operator would then lift the adaptor 22 by hand away from the block 14. The cartridge 16 is removed with the adaptor 22. When readied for operation, the adaptor 22 with the cartridge 16 is tightened to the body with a hand tool to a torque of between 10 IN·LB and 50 IN·LB.
As seen in prior art FIGS. 2A-2B a supply tube 28 is threadably engaged to a supply conduit 30 passing through the block 14 at a first end 31 of the conduit 30. The supply tube 28 carries a shoulder stock 32. The shoulder stock 32 is adjustably coupled to the supply tube 28 by way of a cam stud 34. The cam stud 34 is loosened and tightened by a hand tool. When loosened the stock 32 may be adjusted back and forth along the length of the supply tube 28.
A barrel 36 which can also be called a nipple is threadably engaged with the supply conduit 30 at a second end 33. The barrel 36 carries a hand grip 38. The hand grip is also adjustably coupled to the barrel 36 by way of a cam stud 40. The cam stud 40 is loosened and tightened with a hand tool. When loosened, the grip may be adjusted back and forth along the length of the barrel.